Problem: A jar contains $8$ red marbles, $9$ green marbles, and $6$ blue marbles. If a marble is randomly chosen, what is the probability that it is not green?
Answer: There are $8 + 9 + 6 = 23$ marbles in the jar. There are $9$ green marbles. That means $23 - 9 = 14$ are not green. The probability is $ \frac{14}{23}$.